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Deleted member 26818
- May 5, 2015
- 4,124
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- If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
- United Kingdom
- What type of forum member are you?
- Practising Electrician (Qualified - Domestic or Commercial etc)
- Business Name
- Hendry Electrical Services
Is BigBob1 NetblindPaul in disguise ? They're equally good at generating irrelevant posts, never being wrong and avoiding the answers to very simple questions by spouting an abundance of waffle.
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Deleted member 26818
As it happens I have access to all of the listed publications, though my copy of GN5 is probably out of date.
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Strima
I'll be back in a minute, getting low on popcorn and beer.
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bigbob1
yes consult the DNO. It is their Earth not yours. It’s their TX not yours. It is their engineers that calculate where and when a neutral can be used as CNE.
No if you ask them for permission and they say ‘yes’ then you can. Obviously.
‘
With TT systems, the consumer must provide his or her own connection to Earth, i.e. by installing a suitable earth electrode local to the installation. The circumstances in which a distributor will not provide a means of earthing for the consumer are usually where the distributor cannot guarantee the earth connection back to the source, (IET)
IET. Guidance Note 5: Protection Against Electric Shock, 7th Edition.
That means you are guaranteeing it! But it’s not yours! ESQCR 24 you will be in jail.
installations supplied from TN-C-S (PME) systems, in view of the risk of danger in the event of an open circuit neutral fault on the distributor's low voltage network. ESQCR Regulation 25(2) prevents a distributor from providing a PME supply to premises (IET)
IET. Guidance Note 5: Protection Against Electric Shock, 7th Edition.
ESQCR 25 (2). Taking a DNO supply and provided earthing arrangement out of their specified equipotential zone. Jail.
You do understand that out of all the documents electricians ‘use’ BS7671 is the last one! And it starts with EAWR 89 and ends with ESQCR....with HASAWA and CDM regulations in between...
No if you ask them for permission and they say ‘yes’ then you can. Obviously.
‘
With TT systems, the consumer must provide his or her own connection to Earth, i.e. by installing a suitable earth electrode local to the installation. The circumstances in which a distributor will not provide a means of earthing for the consumer are usually where the distributor cannot guarantee the earth connection back to the source, (IET)
IET. Guidance Note 5: Protection Against Electric Shock, 7th Edition.
That means you are guaranteeing it! But it’s not yours! ESQCR 24 you will be in jail.
installations supplied from TN-C-S (PME) systems, in view of the risk of danger in the event of an open circuit neutral fault on the distributor's low voltage network. ESQCR Regulation 25(2) prevents a distributor from providing a PME supply to premises (IET)
IET. Guidance Note 5: Protection Against Electric Shock, 7th Edition.
ESQCR 25 (2). Taking a DNO supply and provided earthing arrangement out of their specified equipotential zone. Jail.
You do understand that out of all the documents electricians ‘use’ BS7671 is the last one! And it starts with EAWR 89 and ends with ESQCR....with HASAWA and CDM regulations in between...
O
Octopus
Are you EVER going to quote a BS 7671 reg that states clearly that SWA must be earthed at the supply end ?
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bigbob1
I’ll let you in on a little known secret....
While the publisher and contributors believe that the information and guidance given in this work is correct, all parties must rely upon their own skill and judgement when making use of it. The publisher and contributors do not assume any liability to anyone for any loss or damage caused by any error or omission in the work, whether such error or omission is the result of negligence or any other cause. Any and all such liability is disclaimed. (IET)
IET. BS 7671:2018 Requirements for Electrical Installations, IET Wiring Regulations, 18th Edition.
While the publisher and contributors believe that the information and guidance given in this work is correct, all parties must rely upon their own skill and judgement when making use of it. The publisher and contributors do not assume any liability to anyone for any loss or damage caused by any error or omission in the work, whether such error or omission is the result of negligence or any other cause. Any and all such liability is disclaimed. (IET)
IET. BS 7671:2018 Requirements for Electrical Installations, IET Wiring Regulations, 18th Edition.
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bigbob1
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bigbob1
Are you going to ignore ‘manufacturers instructions’? And are you going to let us all know what ‘SWA glands’ are produced for if not to go on SWA cable?
SWA is an extraneous conductive part......go back to college.
134.1.1
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bigbob1
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Deleted member 26818
It is a requirement of ESQCR (Reg 24 I believe) for the DNO to provide consumers a connection point to either the network neutral or protective conductor, for connection of the installation earth.
Regulation 25 allows the DNO to refuse this connection only if the installation fails to comply with BS7671, or could pose a danger or cause an interruption of supply.
Regulation 25 allows the DNO to refuse this connection only if the installation fails to comply with BS7671, or could pose a danger or cause an interruption of supply.
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bigbob1
‘I don’t have to do a risk assessment because it doesn’t say so in the regs’ Said the domestic installer.
114.1
114.1
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Deleted member 26818
- May 5, 2015
- 4,124
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- If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
- United Kingdom
- What type of forum member are you?
- Practising Electrician (Qualified - Domestic or Commercial etc)
- Business Name
- Hendry Electrical Services
B
bigbob1
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bigbob1
So where does it say in the regs you run can export the DNO earth?!
What’s your membership number?
- Feb 25, 2011
- 9,547
- 6,486
- 10,256,798
- If you're a qualified, trainee, or retired electrician - Which country is it that your work will be / is / was aimed at?
- United Kingdom
- What type of forum member are you?
- Practising Electrician (Qualified - Domestic or Commercial etc)
- Business Name
- Richard Burns
My take on this is that any paid work being done, no matter the location, comes under HASAWA and EAWR, this includes domestic properties.
Because the requirements are to maintain safety, this must be done during the works and can be achieved, electrically, by following BS7671.
Therefore, only if there are no changes, after the work has finished it must not present a danger; if it does present a danger then the work that was being done was not, at that time, in accordance with the law.
In that respect the HASAWA and EAWR do apply to the work once it is completed (but most defences would claim later changes had been made!). However when no one is actually working in a domestic property the HASAWA and EAWR do not apply to what is happening in the present, only to the effects that had happened in the past.
Regarding SWA I do not believe it is required to earth the armour, that is not being used as a cpc, at the supply end; it is just best practice. The shorter fault path leads to better compliance with the minimum standards of BS7671 by reducing the impedance of the fault path.
Earthing the armour at both ends, when it is not a cpc, may lead to circulating currents through the armour, but the level of disadvantage must be weighed up against the advantages of having two earthed points on an exposed conductive part.
However where the two ends are in installations with different earthing arrangements then 542.1.3 applies and the supply end only must be earthed.
The default case of the armour as a cpc clearly requires continuity and therefore earthing at both ends.
Because the requirements are to maintain safety, this must be done during the works and can be achieved, electrically, by following BS7671.
Therefore, only if there are no changes, after the work has finished it must not present a danger; if it does present a danger then the work that was being done was not, at that time, in accordance with the law.
In that respect the HASAWA and EAWR do apply to the work once it is completed (but most defences would claim later changes had been made!). However when no one is actually working in a domestic property the HASAWA and EAWR do not apply to what is happening in the present, only to the effects that had happened in the past.
Regarding SWA I do not believe it is required to earth the armour, that is not being used as a cpc, at the supply end; it is just best practice. The shorter fault path leads to better compliance with the minimum standards of BS7671 by reducing the impedance of the fault path.
Earthing the armour at both ends, when it is not a cpc, may lead to circulating currents through the armour, but the level of disadvantage must be weighed up against the advantages of having two earthed points on an exposed conductive part.
However where the two ends are in installations with different earthing arrangements then 542.1.3 applies and the supply end only must be earthed.
The default case of the armour as a cpc clearly requires continuity and therefore earthing at both ends.
O
Octopus
That DOES NOT answer my question, the question that has haunted this thread for pages
Please answer my question ......
W
Wilko
Sorry @bigbob1 but you have gone beyond my simple mind. I've read the references you've kindly provided and I can't see a problem using an already in place TNCS/PME DNO cutout to supply a shed. No going to jail that I can see, provided it's done in accord with our usual BS7671. What have I missed ?
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